A Fairfield doctor who practiced medicine for more than 20 years, most recently out of offices in Stamford and Milford, has pleaded guilty to illegally prescribing oxycodone and defrauding government programs.

Dr. John Katsetos, 53, waived his right to indictment and pleaded guilty May 1 in Hartford federal court to narcotics distribution and health care fraud offenses stemming from his illegal dispensation of oxycodone and other controlled substances well outside of the scope of accepted medical practice.

Katsetos, who was arrested July, 2014 following an investigation that included the use of undercover officers, faces a maximum term of 30 years in prison and fine of up to $1.25 million.